I submitted an entry for the 7DFPS Game Jam. Over the course of a week, I spent a few hours each evening seeing how (if?) I could use my knowledge of Three.js to create a "First-Person (perspective) Shooter" style game.
A link to the result is below. The latest version of the Chrome browser is recommended for viewing. (A postmortem writeup will be available later.)

<disclaimer> While functional, this source code is unpolished, the frame rate isn't great, the collision detection is wonky (jump if you get stuck!) and there is really no objective to this "game" (...but can you get into the room with the star?). Think of this project as more of a preliminary learning experience. </disclaimer>

Option 3: XBox controller. Left joystick = move forwards/backwards/left/right. Right joystick = turn left/right and look up/down. A button = jump. (If the controller is active but not responding, try pressing any button on the controller and refresh the webpage.)